With recent advances in cell transplantation, tissue engineering and genetic technologies, the living cell is becoming an important therapeutic tool in clinical medical care. From the use of living artificial skin and bone material to treat burn and trauma victims, to bioartificial devices and direct transplantation of cellular material to treat the increasingly long list of genetically-based diseases, living cells are increasingly incorporated into comprehensive treatment. In such a construct, the exogenous cells perform the multitude of complex tasks which the diseased tissue cannot. Successful long-term preservation and storage of mammalian cells is critical to the success of this type of medical care. Current preservation technology, including cryobiological technology, often requires rather complicated freezing and thawing protocols which may be specific for cell type, each requiring some variation of a cryopreservation agent (CPA) cocktail to help the cell overcome freezing stresses.
Most traditional cryopreservation protocols include the addition of 1.0-2.0 M of penetrating CPAs such as DMSO, glycerol, and ethylene glycol. Small carbohydrate sugars, such as trehalose, sucrose, and maltose have physicochemical properties (e.g., glass formation) for use as CPAs which are superior to traditional CPAs, however, mammalian cell membranes are not practically permeable to these materials.
In order to provide the preservation of mammalian cells necessary for application of living cells as a therapeutic tool in clinical medical care, new protocols for preserving nucleated cells using low levels of non-toxic preservation agents and having simple procedures applicable to a variety of cells must be developed.